What action should FIA take against Mercedes?

The revelation, early on raceday morning in Monaco, that Mercedes had conducted a three-day tyre test with Pirelli immediately after the F1 circus had performed in Barcelona cast a shadow over the team's subsequent victory in the Principality, but how seriously should the apparent breach be taken by the FIA?

Both Mercedes and Pirelli insist that the test was above board, with the team suggesting its rivals - who claim they knew nothing of the session - should have twigged something was afoot when the Silver Arrows didn't join the usual rush to pack up and leave the Circuit de Catalunya.

While Red Bull and Ferrari both sought clarity on the situation of being able to test 'for' the tyre supplier, it brought a couple of potentially contentious issues to light - namely that Mercedes provided its 2013 car, already known to be struggling with its tyres, and both race drivers for the 1000km run-out, while apparently contravening a 2012 communication from FOTA clarifying that no such test could be carried out 'in season'....

So, were Mercedes and Pirelli misguided in their actions? Did they believe that the session, which apparently followed a request from the tyre supplier to be able to run with a contemporary car, had been approved by the FIA? Were the necessary invitations offered to the other teams to allow them to witness the test? Was Mercedes being offered a helping hand under the auspices of a Pirelli test? Was there an attempt by the team, despite it denying knowledge of what tyres were fitted when, to claw back the deficit to Red Bull?

These are the sorts of questions that the FIA will no doubt be pondering when it convenes to address the protests lodged by both Mercedes' rivals and the report produced by the stewards after speaking to the various parties in Monaco.

But what do you think? Is there a case to answer and, if so, how should the perpetrators be dealt with? Leaving Pirelli out of the equation for the time being, how should Mercedes' involvement be handled by the powers-that-be?

What action should FIA take against Mercedes?

Heavy fineLoss of championship pointsLoss of Monaco victorySuspension from world championshipDenied participation in Canadian GPNo action need be taken by FIA